It is known that the saccharide component of the cell walls of yeasts and fungi is constituted mainly by glucans and mannans; the polysaccharides which can be obtained from Saccharomyces cerevisiae are of particular interest in the food field since this micro-organism has been used by man in food for centuries and therefore offers the best guarantee of being harmless.
The cell walls of Saccharomyces cerevisiae are composed mainly of glucan which in turn is constituted by a main chain of glucose units joined by B(1-3) glucoside bonds with a low degree of inter- and intramolecular branching by means of B(1-6) glucoside bonds.
The polysaccharides contained in the walls of Saccharomyces cerevisiae can be obtained with a high degree of purity by various methods such as, for example, those described in U.S. Pat. Nos. 5,082,936 and 3,867,554 and in Italian patent application MI96A000681.
The use of these substances as thickeners for food preparations such as creams, ices, sauces, etc. has been proposed because of their ability to absorb and retain large quantities of water and to increase viscosity. Moreover, when added to substantially liquid food products, they cause these products to produce a sensation of a fatty consistency when tasted, even though these polysaccharides are substantially fat free.